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    Show HN: TinyPilot – Build a KVM over IP using a Raspberry Pi

    (mtlynch.io)
    756 points mtlynch | 15 comments | 23 Jul 20 13:56 UTC | HN request time: 1.049s | source | bottom
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    dukoid ◴[23 Jul 20 15:27 UTC] No.23928345[source]▶
    I have given up on KVMs altogether and I am using the following approach now:

    - Most monitors have multiple digital inputs. Connect each computer to one of them

    - Use a USB switch keyboard and mouse

    - Before switching the USB switch, press the "lock screen" key combination and make sure locking the screen drops the video signal

    - After switching the USB switch, pressing shift should bring up the login dialog and re-activate video output. Since the monitor has just lost the signal in the previous step, it will scan the inputs and switch to the desired signal.

    replies(5): >>23928396 #>>23928658 #>>23928780 #>>23931262 #>>23934346 #
    1. _1qd4 ◴[23 Jul 20 15:32 UTC] No.23928396[source]▶
    I did this for a while, the problem is that there's really no such thing as a high-quality USB switch. They are all garbage and mess with USB devices in some way (at least at the consumer level).
    replies(4): >>23928442 #>>23928587 #>>23929853 #>>23953292 #
    2. GordonS ◴[23 Jul 20 15:37 UTC] No.23928442[source]▶
    I switched from a KVM to a USB switch a few years back, and haven't had any real issues with it. I don't think it was expensive either, just a standard USB 3 switch with only 2 ports. Occasionally it takes more than a few seconds after pressing the button for the switch to happen, but that's about it.
    replies(1): >>23928539 #
    3. BoysenberryPi ◴[23 Jul 20 15:44 UTC] No.23928539[source]▶
    This is my experience as well. I currently use a USB switch that I got off of Amazon for about 15 bucks. It typically "just works." Press the button, wait 2 seconds and my input devices have switched.
    replies(1): >>23928632 #
    4. btgeekboy ◴[23 Jul 20 15:48 UTC] No.23928587[source]▶
    I have an old Belkin USB 2.0 switch from god-knows when that works beautifully. I use it to share a hub with a keyboard and mouse attached. I’ve given up trying to find a 4K60 x2 DisplayPort KVM that doesn’t suck.
    replies(2): >>23929161 #>>23929546 #
    5. TacticalTable ◴[23 Jul 20 15:51 UTC] No.23928632{3}[source]▶
    Care to share it? The one I have will work for a few switches, then both Windows/Mac will eventually stop recognizing the port its connected to until a reboot.
    replies(2): >>23928861 #>>23937935 #
    6. HEHENE ◴[23 Jul 20 16:09 UTC] No.23928861{4}[source]▶
    I have been using one from IOGEAR (SKU GUS432CA1KIT) for the last 6 months and I haven't had a single problem with it.

    I use it to switch all of my peripherals (keyboard, mouse, wireless headset dongle, webcam, and mixer) between my desktop and my MacBook several times per day and have not had a single failure yet.

    7. stamps ◴[23 Jul 20 16:36 UTC] No.23929161[source]▶
    I have this one[0] that works great.

    Wendell at Level1Techs does good work and there's even newer ones that can do 8k30.

    [0] https://store.level1techs.com/products/kvm-switch-dual-monit...

    replies(1): >>23931156 #
    8. bombita ◴[23 Jul 20 17:08 UTC] No.23929546[source]▶
    I have been using this at 4k60 (but 1 monitor) flawlessly for 8 months.

    https://www.startech.com/Server-Management/KVM-Switches/2-po...

    replies(1): >>23929837 #
    9. duskwuff ◴[23 Jul 20 17:31 UTC] No.23929837{3}[source]▶
    Seconding a recommendation for Startech's KVMs. They have an excellent USB stack which handles complex USB hierarchies flawlessly -- I've successfully used mine with chained hubs, weird HID devices like Apple keyboards, and non-HID devices like disks, audio interfaces, and even stranger things.
    10. JeremyNT ◴[23 Jul 20 17:32 UTC] No.23929853[source]▶
    > I did this for a while, the problem is that there's really no such thing as a high-quality USB switch. They are all garbage and mess with USB devices in some way (at least at the consumer level).

    A lot of these things seem to "help" by inserting their own USB host device that acts as a proxy for attached USB peripherals. This allows them to do (ostensibly) useful useful things such as intercepting keypresses and responding to them (e.g. by switching to another input).

    Don't get one of those, get a physical switch that just connects the leads to the correct port when pressed. I got this USB 2.0 switch (all you need for input devices) for $12 [0]. I'm sure there are others available with more ports, but this is all I needed.

    [0] https://www.amazon.com/gp/product/B01HV1N674

    replies(1): >>23929961 #
    11. weaksauce ◴[23 Jul 20 17:41 UTC] No.23929961[source]▶
    Yeah I second this. I have a physical usb switch to move keyboard and mouse over. It works flawlessly.

    Though, I also use a KVM to switch over the video but it's separate.

    12. ajford ◴[23 Jul 20 19:17 UTC] No.23931156{3}[source]▶
    I couldn't find the details on their site, but do you know whether the 3.5mm audio jack is 3 or 4 pole? I've found that most KVMs have the 3 pole jack, meaning it just supports audio out, but I need 4-pole so my headset microphone works.
    replies(1): >>23938114 #
    13. GordonS ◴[24 Jul 20 10:51 UTC] No.23937935{4}[source]▶
    One I use is a brand called "Plugable". I don't think they still make the model I have, but they have a newer version of the same: https://plugable.com/products/usb3-switch2

    I've used it with Windows 10, MacOS and an RPi, with no issues.

    14. lathiat ◴[24 Jul 20 11:18 UTC] No.23938114{4}[source]▶
    You can get USB audio dongles that have that. Which could then switch on the KVM instead.
    15. hakfoo ◴[25 Jul 20 23:57 UTC] No.23953292[source]▶
    The USB side always worked fine for me. The problems tended to be mostly video related.

    I have a HDMI KVM switch that's supposed to be 4k@60. One PC won't detect it as such; I can make a custom 1440p at 42Hz mode but nothing higher. The other will send 4k/@60, but the monitor will do one of 4 or so failure modes:

    * Entire screen compressed to half width: 50% * Correct behaviour: 20% * Correct display, occasionally flipping to black screen: 10% * Gatbled screen: 5% * No synch: 15%

    Switching input is a game of toggling back and forth until it synchs correctly.

    None of this happens with a direct connection.

    The switch also doesn't seem to detect when I set up a keyboard macro for the switch-input sequence (control-control-1/2/3/4) but that's not nearly the dealbreaker.

    I'm not sure if it's the switch or the monitor being relatively intolerant of the switch's behaviour, but I don't want to toss around $100-300 on spares to diagnose this.